I need to connect a 40mm waste pipe to a soil stack; never had to do this before.
Is it simply a matter of attaching a soil strap boss: http://www.screwfix.com/app/sfd/cat/pro.jsp?idI547&tsa172
with appropriate rubber adaptor inside the boss: http://www.screwfix.com/app/sfd/cat/pro.jsp?id 481&tsa227
having first drilled a hole in the side of the stack?
How does this work - is there a seal between the boss and the soil pipe? What size hole to form in the soil pipe - does the 40mm butt up agaist the outside of the pipe, or protrude into it? Or do you try to get it flush with the internal bore of the soil pipe?
The plan would be for the junction to be a few inches below where the toilet effluent enters the stack - is that an issue?